Fig. 6: Light regulates IAA metabolism by suppressing COP1 function.
a Light suppresses the COP1-mediated K63 ubiquitination of GH3.5. Col, GH3.5-GFP, and GH3.5-GFP/cop1-4 seedlings were grown in continuous darkness or continuous white light (35 μmol m−2 s−1) for 4 days. Immunoprecipitated GH3.5-GFP proteins were detected with anti-K63 Ub and anti-GFP antibodies. The asterisk indicates a non-specific band. HSP was used as a loading control. D, continuous darkness; L, continuous white light. b–e Content of endogenous IAA, IAA-Asp, oxIAA-Asp, and IAA-Asp + oxIAA-Asp in the dark or light. Whole seedlings grown for 4 days in the dark or light (35 μmol m−2 s−1) were used to measure IAA, IAA-Asp and oxIAA-Asp contents. cD, continuous darkness; cWL, continuous white light. Data are presented as the mean ± SD (n = number of biological replicates). Different lowercase letters above the histogram represent statistically significant differences (P < 0.05) determined by ordinary two-way ANOVA with Tukey’s post hoc test. Source data are provided as a Source Data file.
